Bar code marking the surface of an object

ABSTRACT

A plurality of individual marks are imprinted in the surface of an object to form a plurality of substantially linear, rectangular arrays of preselected width in the surface of the object. Each imprinted substantially linear, rectangular array is spaced a preselected distance from each adjacent imprinted, substantially linear, rectangular array to provide a space of preselected width. The preselected width substantially linear, rectangular arrays and preselected width spaces are combined in alternating fashion to provide a bar code message in the surface of the object.

CROSS REFERENCE TO RELATED APPLICATIONS

The application is a continuation of copending application Ser. No.011,061, now U.S. Pat. No. 4,510,867, filed on Feb. 4, 1987, entitled,"Bar Code Marking The Surface Of An Object" by Edwin W. Speicher.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a method for marking the surface of an object,and more particularly, to a method for selectively imprinting aplurality of individual marks in the surface of an object to form a barcode message in the surface of the object.

2. Description of the Prior Art

Utilizing a dot matrix marking device that includes a plurality ofindividual marking pins to imprint alphanumeric characters in thesurface of a workpiece is well known.

British Pat. No. 2,002,694 discloses a programmable dot matrix type ofengraver that is operable to imprint a selected size of alphanumericcharacters into the surface of a workpiece. An engraving tool issupported on an arm which is movable on a carriage by a lead screwrotated by a stepping motor. The carriage is movably mounted on ahorizontal arm that is, in turn, supported by a vertical column above abase on which the workpiece to be marked is stationarily positioned.With this arrangement, the engraving tool is movable along horizontal xand y axes. The engraving tool includes a punch which is remotelycontrolled by a central processing unit through a solenoid operated airvalve to imprint the desired alphanumeric character into the surface ofa workpiece.

U.S. Pat. No. 4,506,999 discloses a pneumatically controlled apparatusthat includes an array of seven pins that are selectively operated toimprint alphanumeric characters in a workpiece. The seven pins are movedacross the workpiece to selectively mark the workpiece with the desiredalphanumeric characters. The angular arrangement of the pins determinesthe height of the characters and rotation of the head adjusts the angleof the line of pins.

While it has been suggested by the prior art devices to utilize aplurality of marking pins to imprint a plurality of individual marks inthe surface of a workpiece to form an alphanumeric character messagethereon, there is a need for a method of utilizing a plurality ofmarking pins to imprint a plurality of individual marks in the surfaceif a workpiece to provide a bar code message in the surface of theworkpiece. The bar code message must be imprinted in the surface of theworkpiece in such a manner that the message is capable of being read bystandard, commercially obtainable bar code reading devices.

SUMMARY OF THE INVENTION

In accordance with the present invention there is provided a method forimprinting a bar code message in the surface of an object that includesthe step of imprinting a plurality of individual marks in the surface ofthe object arranged to form a plurality of substantially linear,rectangular arrays of preselected width.

Further in accordance with the present invention there is provided amethod for spacing each imprinted substantially linear, rectangulararray from each adjacent imprinted substantially linear, rectangulararray a preselected distance on the surface of an object to provide aspace of preselected width.

Additionally in accordance with the present invention there is provideda method for combining the preselected width substantially linear,rectangular arrays and the preselected width spaces between adjacentsubstantially linear, rectangular arrays in alternating fashion toprovide a bar code message imprinted in the surface of an object.

Accordingly, the principal object of the present invention is to providea method for imprinting in the surface of an object a plurality ofindividual marks arranged to form a plurality of preselected width,substantially linear, rectangular arrays.

Another object of the present invention is to provide a method forspacing each imprinted substantially linear, rectangular array from eachadjacent substantially linear, rectangular array a preselected distanceon the surface of an object to provide a space of preselected width.

An additional object of the present invention is to provide a method forcombining preselected width substantially linear, rectangular arrays andpreselected width spaces in alternating fashion to provide a bar codemessage imprinted in the surface of an object.

These and other objects of the present invention will be more completelydisclosed and described in the following specification, the accompanyingdrawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view in side elevation of a marking machine illustrating amarking device supported on a base of the machine in vertical positionfor selective movement for imprinting a plurality of substantiallylinear, rectangular arrays in the surface of an object and a tableassembly positioned on the marking machine fixed base member forsupporting an object to be marked.

FIG. 2 is an illustration of a three-of-nine bar code messagerepresenting the alphanumeric message B2C3, reproduced from AmericanNational Standard, MH10.8M-1983, page 9.

FIG. 3 is an illustration of a three-of-nine bar code message imprintedin the surface of an object that represents the alphanumeric message123.

FIG. 4 is an enlarged view of a portion of an elongated widthsubstantially linear, rectangular array.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 2 there is illustrated a bar code message generallydesignated by the numeral 10 which has been reproduced from AmericanNational Standard MH10.8M-1983, page 9. Bar code message 10 is anexample of a typical bar code message that may be printed on a tag orlabel and affixed to an object for object identification purposes.

The bar code message generally designated by the numeral 10 is referredto in the bar code marking industry as a three-of-nine bar code pattern.A list of all alphanumeric characters capable of representation by athree-of-nine bar code pattern is illustrated in American NationalStandard MH10.8N-1983, page 10 (not shown).

As seen in FIG. 2, bar code message 10 is composed of an alternatingseries of bars and spaces. A bar may be of narrow width 21 or elongatedwidth 24. A space may be of narrow width 23 or elongated width 22.Elongated width bar 24 and elongated width space 22 are of relativelyequal width. Narrow width bar 21 and narrow width space 23 are also ofrelatively equal width.

Every narrow and elongated width bar and space illustrated in FIG. 2 isreferred to as an element. The proper combination of nine elementsrepresents an alpha or numeric character. The combination of nineelements 26 represents the letter B. Elements 27, 28 and 29 representthe alphanumeric characters 2, C and 3. Nine elements 25, whichrepresent the character asterisk, are placed at the beginning and end ofthe bar code message to identify the start and stop of the bar codemessage. Any common symbol may be used for this purpose.

Since bar code message 10 is composed of three-of-nine characters, eachof the characters 25-29 is composed of nine elements. Of the nineelements, five elements are bars and four elements are spaces. In athree-of-nine bar code pattern, three of the nine elements which make upany character are of elongated width and the remaining six elements areof narrow width. The nominal ratio of the width of an elongated elementto the width of a narrow element should fall within the range of 2:1 to3:1. Each nine element character is separated from each adjacent nineelement character by narrow width space 23. Although a narrow widthspace 23 is used in FIG. 2 to separate adjacent characters, an elongatedwidth space can also be used with identical results. Element height,generally designated by the numeral 41, can be varied to suit particularapplication requirements.

As previously mentioned, the bar code message generally designated bythe numeral 10 in FIG. 2 may be printed on a tag or label and affixed toan object by suitable means.

A bar code message which is imprinted directly in the surface of anobject is illustrated in FIG. 3. The bar code message generallydesignated by the numeral 50 in FIG. 3 is imprinted directly in thesurface of an object to, among other things, simplify the bar codemarking process and eliminate the problems associated with lost ordamaged bar coded tags and labels. Bar code message 50 may be imprinteddirectly into the surface of many types of objects that includeproduction line items, such as slabs, rolled stock and the like, as wellas plates, round and various tags, components and parts fabricated ofmaterial which may be comprised of glass, metal or plastic.

The bar code message generally designated by the numeral 50 in FIG. 3which is imprinted in the surface of an object is composed of thethree-of-nine bar code characters previously described. It should beunderstood that although FIG. 3 illustrates a three-of-nine bar codemessage imprinted in the surface of an object, a bar code messageutilizing any standard bar code pattern may be imprinted with identicalresults. Bar code message 50 is composed of an alternating series ofbars and spaces. A bar may be of narrow width 73 or elongated width 72.A space may be of narrow width 71 or elongated width 74.

As seen in FIG. 3, each narrow width space 71 and elongated width space74 is comprised of a plurality of individual marks 83 arranged to form asubstantially linear, rectangular array of preselected width in thesurface of the object. Each substantially linear, rectangular array isreferred to as an array. The width of the array imprinted in the surfaceof the object is controlled by selecting the number of columns 82 ofindividually imprinted marks 83 which make up the array. Each array,whether of narrow or elongated width, is imprinted in the surface of theobject a preselected distance from each adjacent array to control thewidth of the bar element which is located between each pair of adjacentarrays. The bar element is represented by the spacing between adjacentarrays. For example, narrow width bar 73 and elongated width bar 72 inFIG. 3 correspond to narrow width bar 21 and elongated width bar 24 inFIG. 2. Similarly, narrow width space 71 and elongated width space 74 inFIG. 3 correspond to narrow width space 23 and elongated width space 22in FIG. 2. Although the bar code message 50 shown in FIG. 3 illustratesall bar elements as preselected width spaces between adjacent arrays andall space elements as preselected width arrays, this is a matter ofsystem designer choice. If desired, all bar elements may be comprised ofpreselected width arrays and all space elements may be comprised of thepreselected width spaces between adjacent arrays.

As seen in FIG. 3, narrow width array 71, which represents a narrowwidth space, consists of one column 82 of nine individually imprintedmarks 83. Elongated width array 74, which represents an elongated widthspace, consists of three columns 82 of nine individually imprinted marks83. The selection of one column 82 of individually imprinted marks 83for narrow width array 71 and three columns 82 of individually imprintedmarks 83 for elongated width array 74 is a matter of system designerchoice. As with any three-of-nine bar code pattern, the nominal ratio ofthe width of an elongated array to the width of a narrow array shouldfall within the range of 2:1 to 3:1. As seen, controlling the spacingbetween adjacent arrays controls the width of the bar between adjacentarrays. Each array is spaced a preselected distance from each adjacentarray so that the ratio of the width of an elongated width bar to thewidth of a narrow width bar also falls within the range of 2:1 to 3:1.

As previously described, a space may be of narrow width as illustratedby array 71 or elongated width as illustrated by array 74. A bar may beof narrow width 73 or elongated width 72. The narrow width spaceillustrated by array 71 and narrow width bar 73 are of relatively equalwidth. Similarly, elongated width space illustrated by array 74 andelongated width bar 72 are of relatively equal width. As previouslydescribed, the width of the bars between adjacent arrays is controlledby controlling the distance between pairs of adjacent arrays imprintedin the surface of the object.

Each narrow and elongated width array space and bar illustrated in FIG.3 is referred to as an element. As in any three-of-nine bar codepattern, nine elements comprise an alpha or numeric character. Thecombination of nine elements 76 represents the numeral 1. Elements 77and 78 represent the numerals 2 and 3, respectively. The nine elements75 represent the start and stop character asterisk. Each nine elementcharacter is separated from each adjacent nine element character by anelongated width array space 74.

As described, the bar code message 50 in FIG. 3 may be imprinteddirectly in the surface of an object to eliminate the need for bar codedtags or labels.

Referring to FIG. 4, there is illustrated an enlarged portion of anelongated width array generally designated by the numeral 100. Twocolumns 82 of individually imprinted marks 83 are shown. In order forelongated width array space element 74 shown in FIG. 3 to functionallyrepresent elongated width space element 22 shown in FIG. 2, eachindividual mark 83 must be imprinted in the surface of the object sothat the density of the individually imprinted marks 83 in elongatedwidth array space element 74 is maximized.

To accomplish this, each individual mark 83 in elongated width arrayspace element 74 must be imprinted in the surface of the object in atleast a juxtaposed relation to every adjacent imprinted mark 83 in thearray. Juxtaposed is here defined as to place side by side as intouching. At a minimum, to achieve optimum placement of the individualmarks 83 in any particular column 82, each individual mark 83 in thecolumn should be imprinted in abutting relation to each adjacentindividual mark in the column. Similarly, to achieve optimum placementof the individual marks 83 in any particular row of marks 83 inelongated width space element 74, each individual mark 83 in aparticular row should be imprinted in abutting relation to eachhorizontally adjacent individual mark 83 in the row. Preferably, allindividually imprinted marks 83 in elongated width array space element74 should be imprinted in the surface of the object to provide apreselected minimum amount of overlap between all vertically adjacentmarks 83 and a preselected minimum amount of overlap between allhorizontally adjacent marks 83. Imprinting all vertically andhorizontally adjacent individual marks 83 in juxtaposed or overlappingrelation will ensure that the density of the individually imprintedmarks 83 in elongated width array space element 74 is maximized.Maximizing the density of the individually imprinted marks 83 inelongated width array space element 74 will provide an elongated widtharray space element 74 that functionally represents elongated width bar24 shown in FIG. 2. Maximizing the density of the individually imprintedmarks in array 74 decreases the possibility of detection errors when barcode message 50 is read by a standard commercially obtainable bar codereader device.

As seen in FIG. 4, when vertically adjacent individually imprinted marks83 are not imprinted in the surface of the object in juxtaposed oroverlapping relation, vertical dimension x between vertically adjacentimprinted marks 83 is produced. Similarly, when horizontally adjacentimprinted marks 83 are not imprinted in the surface of an object injuxtaposed or overlapping relation, horizontal dimension y betweenhorizontally adjacent imprinted marks 83 is also produced. As bothvertical dimension x and horizontal dimension y, appear in elongatedwidth array 74, the density of the individually imprinted marks 83 inthe elongated width array space element 74 is decreased. Also, as thevertical dimension x between vertically adjacent individually imprintedmarks 83 and the horizontal dimension y between horizontally adjacentindividually imprinted marks 83 increase, the area of shaded zone zincreases. Shaded zone z represents an area of imperfection formed byand contained within four individually imprinted marks 83. As verticaldimension x, horizontal dimension y and the area shaded zone z increase,the density of the individual imprinted marks 83 in elongated widthspace element 74 is decreased. A decrease in the density of theindividually imprinted marks 83 in elongated width array space element74 may result in possible detection errors when the bar code is read bystandard commercially obtainable bar code reading devices, since the barcode reading device may inadvertantly interpret the spacing betweenindividually imprinted marks 83 in elongated width array space element74 as a bar element such as narrow width bar 73 or elongated width bar72 shown in FIG. 3.

Referring to FIG. 3, it can be seen that the three columns 82 ofindividual marks 83 in elongated width array space element 74 areimprinted in the surface of an object in a substantially verticalposition. Similarly, the one column 82 of individually imprinted marks83 in narrow width array space element 71 is also imprinted in thesurface of an object in a substantially vertical position. Every column82 of individually imprinted marks 83 in either a narrow width arrayspace element 71 or elongated width array or elongated width array spaceelement 74 should be positioned substantially vertically in the surfaceof the object to ensure that the spacing between arrays, whichrepresents a bar element, maintains a relatively rectangular shape.Maintaining the verticality of the individual columns 82 of individuallyimprinted marks 83 will also eliminate detection errors when the barcode is read by standard, commercially obtainable bar code readingdevices.

An apparatus suitable for imprinting the bar code message 50 shown inFIG. 3 is illustrated in FIG. 1 and generally designated by the numeral110. This suitable apparatus is also disclosed in U.S. Pat. No.4,591,279, which patent is hereby incorporated by reference. Apparatus110 is used to imprint in the surface of an object a plurality ofindividual marks 83 arranged in a plurality of substantially linear,rectangular arrays to produce bar code message 50.

As seen in FIG. 1, marking apparatus 110 is mounted for verticalmovement on a support system generally designated by numeral 116 thatincludes a pair of spaced apart vertically extending posts, one shown at118, which are supported by two pedestals, one shown at 122. Verticallyextending posts 118 and support pedestals 122 connect marking apparatus110 to fixed member 126. Marking device 114 is supported by a generallyU-shaped support member consisting of intermediate plate portion 148,base plate portion 150, and support plate portion 176. Base plateportion 150 and support plate portion 176 extend from intermediate plateportion 148 in generally parallel spaced relation to each other. TheU-shaped support member is slideably secured to vertical posts 118 byfastening means 140 in such a manner that base plate portion 150 extendssubstantially parallel to fixed member 126 horizontal surface. TheU-shaped support member which supports marking device 114 movesvertically relative to fixed member 126 and can be positioned at anydesired distance above fixed member 126.

Two guide means 168 secured to the generally U-shaped support membersupport marking device 114. Guide means 168 support marking device 114as it is moved in a linear direction by drive means (not shown) relativeto the generally U-shaped support member. Pivoting means 136 andindexing means 138 operate to allow marking device 114 to be pivoted ina horizontal plane relative to guide means 156 to provide a preselectedangle between guide means 156 longitudinal axis and marking device 114longitudinal axis. Varying this angle provides a means for adjusting thewidth and height of the plurality of rectangular arrays imprinted in thesurface of an object. The angle between marking device 114 and guidemeans 156 should be adjusted so that, as marking device 114 operates,each individual mark 83 in each rectangular array is imprinted in thesurface of an object in juxtaposed or overlapping relation to eachadjacent individual mark 83 in the array.

Table assembly 240, also disclosed in U.S. Pat. No. 4,591,279 and herebyincorporated by reference, is mounted to fixed member 126. Tableassembly 240 can be used in conjunction with marking apparatus 110 toprovide multiple row marking on the surface of object 248. Table 240stationery base assembly 242 is adapted to the bolted to fixed member126 by bolting means 246 so that movable table assembly upper portion244 reciprocates on an axis perpendicular to the direction of movementof marking device 114. An object to be marked 248 is placed on movabletable assembly upper portion 244 and secured thereon by suitable means(not shown). Movable table assembly upper portion 244 has a drive means245 which allows table assembly upper portion 244 to be positioned at apreselected location on stationary base assembly 242. Movable tableassembly upper portion 244 and marking device 114 can be positioned atany preselected point along their respective axes of travel by suitablecontrol means to imprint a plurality of spaced apart rectangular arraysat any desired location on the surface of object 248.

If it is desired to provide multiple row marking on the surface ofobject 248, marking device 114 is first operated to selectively imprintin the surface of object 248 a plurality of rectangular arraysselectively spaced from each other to represent, for example, bar codemessage 50 shown in FIG. 3. After marking device 114 has imprinted barcode message 50, marking device 114 drive means can be operated tocommunicate through suitable control means with movable table assemblyupper portion 244 drive means to allow movable table assembly upperportion 244 to reciprocate a preselected distance perpendicular to thedirection of movement of marking device 114. After movable tableassembly upper portion 244 has reciprocated this further perpendiculardistance, marking device 114 can be operated to imprint the alphanumericequivalent of the bar code message or any desired message either aboveor beneath bar code message 50.

According to the provisions of the patent statutes, I have explained theprinciple, preferred construction and mode of operation of my inventionand have illustrated and described what I now consider to represent itsbest embodiments. However, it should be understood that, within thescope of the appended claims, the invention may be practiced otherwisethan as specifically illustrated and described.

I claim:
 1. A method for imprinting a machine readable bar code message in the surface of an object comprising the steps of;providing an object, imprinting a plurality of marks by indenting the surface of said object and forming recesses therein, said plurality of marks arranged in a plurality of substantially linear, rectangular arrays in the surface of said object, spacing each imprinted substantially linear, rectangular array a preselected distance from each adjacent imprinted, substantially linear, rectangular array to provide a machine readable bar code message imprinted in the surface of each object, and positioning each of said marks so that the adjacent edges of each of said marks are in juxtaposition with each other to thereby maximize the density of said plurality of marks imprinted within each said substantially linear, rectangular array to minimize errors in reading said machine readable bar code message.
 2. A method for imprinting a machine readable bar code message in surface of an object as set forth in claim 1 including;controlling the width of a substantially linear, rectangular array by selecting the number of columns of imprinted marks which make up said substantially linear, rectangular array.
 3. A method for imprinting a machine readable bar code message in the surface of an object as set forth in claim 2 including;imprinting each mark within each said substantially linear, rectangular array to provide a preselected minimum amount of overlap between all vertically adjacent marks and a preselected minimum amount of overlap between all horizontally adjacent marks.
 4. A method for imprinting a machine readable bar code message in the surface of an object as set forth in claim 2 including;controlling the spacing between any two adjacent substantially linear, rectangular arrays to obtain a space of preselected width.
 5. A method for imprinting a machine readable bar code message in the surface of an object as set forth in claim 4 including;combining said preselected width substantially linear, rectangular arrays with said preselected width spaces in alternating fashion to provide a machine readable bar code message imprinted in the surface of said object.
 6. A method for imprinting a machine readable bar code message in the surface of an object as set forth in claim 1 including;providing a marking device having a longitudinal axis to imprint said plurality of marks; providing guide means to movably suport said marking device, said guide means having longitudinal axis being in angular relationship with said marking device longitudinal axis; and adjusting said angular relationship between said guide means longitudinal axis and said marking device longitudinal axis to provide for maximal density of said plurality of marks imprinted within each said substantially linear, rectangular array in said machine readable bar code message.
 7. A method for imprinting a machine readable bar code message in the surface of an object as set forth in claim 6 including,securely placing said object to be imprinted with a machine readable bar code message on a movable tabele assembly upper portion; positioning said movable table assembly upper portion and said marking device to imprint said machine readable bar code message at a preselected location on said object surface.
 8. A method for imprinting a machine readable bar code message in the surface of an object as set forth in claim 7 including;reciprocally moving said movable table assembly upper portion a preselected distance perpendicular to the direction of movement of said marking device after said object has been imprinted with a machine readable bar code message, and imprinting an alphanumeric message on said object. 